Where does “nonaccessible” come from?

nonaccessible (English) comes from English accessible, from French accessible, from Latin accessibilis, from Latin accessus, from Latin accēdō, from Latin ad-, from Latin īn-, from Latin în — in.

Ancestry of “nonaccessible”, step by step

nonaccessible traces back through two separate lines of ancestry.

via English accessible

StepLanguageWordMeaning
1EnglishaccessibleEasy of access or approach; Built or designed as...
2Frenchaccessibleaccessible, attainable, obtainable, available;...
3Latinaccessibilisapproachable; accessible
4Latinaccessusapproached, reached; advanced, attacked;...
5Latinaccēdōto go or come toward, approach, reach
6Latinad-to; usually prefixed to verbs, in which cases it...
7Latinīn-un-, non-, not
8Latinînin, at, on, upon, from (space)
9Latinenlookǃ beholdǃ; reallyǃ?; come onǃ
10Proto-Italicenin
11Proto-Indo-Europeanh₁énin

via English non

StepLanguageWordMeaning
1EnglishnonObsolete form of none
2Frenchnonno; not; a no, a negative response
3Old Frenchnonno; not; Alternative form of nom
4Latinnōnnot
5Old Latinnoenum
6Proto-Indo-Europeanóynosone; single
Every word from Proto-Indo-European h₁én